Which of the following are not quadratic polynomials?
(i) 3+4x–7x2
(ii) 8x2–15
(iii) 6x – 15
(iv) 4x3–3x
(v) x2–x+1
i) 3+4x–7x2 is a polynomial of degree 2, so it is a quadratic polynomial.
ii) 8x2–15 is a polynomial of degree 2, so it is a quadratic polynomial.
iii) 6x – 15 is not a polynomial of degree 2, so it is not a quadratic polynomial.
iv) 4x3–3x is a polynomial of degree 3, so it is not a quadratic polynomial.
v) x2–x+1 is a polynomial of degree 2, so it is a quadratic polynomial.